The present invention relates to a connector or fastening element for osteosynthesis, particularly for fastening bone fragments using a support plate.
Depending on the type of bone fracture, draw-in bolts are used directly or in combination with support plates for fixing bone fragments. Depending upon the location in which they are to be used, cortical or spongiosal screws which have different forms of thread are used. The spongiosal screws have a very pronounced, deep thread in order to achieve an adequate hold in the very soft bone tissue. The disadvantage of these screws, however, is that they are very difficult to unscrew, particularly from the cortical substance, once the fracture has mended. A further disadvantage in directly fastening bones together, using screws is that the direct connection between the screw and the bone is inflexible. Brief overstressing of the bone results in damage to the connection, which can lead to loosening the screws or possibly even breaking out.
Connectors of the foregoing type are known. One of such connectors is disclosed in applicant's U.S. Pat. No. 3,678,925.